This project is designed to prepare a GMP quality investigational HIV vaccine and complete the preclinical, laboratory and long-term product stability studies needed to begin and maintain clinical trials. The Vaccine Research Center (VRC), NIAID is developing a novel prime-boost HIV vaccine strategy directed at the three most globally prevalent HIV subtypes (clades). VRC's HIV prime-boost candidate is designed to elicit immune responses to HIV sequences from clades A, B and C which together cause about 90 percent of incident HIV infections around the world. This product has since been evaluated clinically as a single agent and as part of a DNA prime-adenovector boost regimen in over 1000 study subjects in several Phase 1 and 2 clinical trials in U.S. and international sites. Production of Phase II materials has been completed and stability studies continue to support on-going clinical trials..